Four optically active cycloheptatriene derivatives carrying a methoxy group(s) at different positions were prepared by the 2,4-pentanediol-tethered Buchner reaction. In addition to the high stereoselectivity, the tetheralso controlled the regioselectivity in a good-to-high degree. Some of the products are unstable under acidic conditions, resulting in isomerization through a prototropic reaction or aromatization
CP-225,917 synthetic studies: unusual hydroboration regioselectivity influenced by remote functional groups
作者:James A. Ashenhurst、James L. Gleason
DOI:10.1016/j.tetlet.2007.11.118
日期:2008.1
Hydroboration–oxidation of 1,1-disubstituted alkenes with borane–methylsulfide complex in bridged tricyclic intermediates of the CP-225,917 ring system were observed to produce significant quantities of tertiary alcohol products. This net Markovnikov addition of water across an alkene is influenced by a combination of remote functional groups. Computations at the B3LYP/6-31G∗ level of theory correctly